A Continental Polar (CP)air Mass Moves into the Territory Occupied

A continental polar (cP) air mass moves into the territory occupied a continental tropical (cT) air mass. What is likely to happen?

A) The air masses mix creating an air mass of average temperature.
B) A cold front forms at the boundary between the two air masses.
C) A cold front extends from the boundary zone into the territory occupied by the continental tropical (cT) air mass.
D) A stationary front forms.